In a principal aspect, the present invention relates to an improved water brake dynamometer and, more particularly, to a water brake dynamometer having an improved control valve mechanism for controlling water circulation through the water brake.
Heretofore it has been known that dynamometers, including water brake dynamometers, provide an accurate and economical way to test engines. Torque and speed of an engine are measured accurately and precisely by such devices in order to provide a means for adjusting the engine for maximum power output.
In the agricultural field, various types of dynamometers have been suggested including that disclosed in the patent to Ellsworth W. Lapp, et al, U.S. Pat. Nos. 2,981,099, and Melvin Bonomo, 4,062,233. Known dynamometers have proven to be very useful and efficient. However, the advent of improved and more powerful engines for agricultural use necessitates an improved dynamometer.
A type of dynamometer believed to be adaptable for agricultural use is a water brake dynamometer. Water brake dynamometers are generally disclosed in the Society of Automotive Engineers Publication No. 710215 dated Jan. 11-15, 1971 entitled "High Speed Dynamometers--Modern Water Brakes Offer New Potential For Testing Engineers" by W. C. Bronder and Charles S. Jewitt. Dynamometers of this general nature are also disclosed in the patent to Taylor, U.S. Pat. No. 2,035,576 entitled "Dynamometer", issued Mar. 31, l936, and the patent to Cline, U.S. Pat. No. 2,634,830 entitled "Apparatus and Method for Controlling Dynamometers", issued Apr. 14, l953.
U.S. Pat. Nos. 2,035,576 and 2,634,830 disclose momentum interaction dynamometers wherein torque is transferred between a rotor and a stator element by means of directed fluid flow between sectors of the rotor and the stator. In the patent issued to Cline, momentum interaction or fluid transfer is effected by means of blade members associated with a rotor directing fluid against cooperative blade members associated with a stator. In the Taylor patent, the rotor and stator are comprised of flat discs having surfaces in opposed relation. Variously sized pie-shaped segments are formed in the surface of the discs. Momentum interaction is effected by transfer of fluid from one of the pie-shaped segments toward a separate pie-shaped segment upon rotation of the rotor with respect to the stator.
The Taylor patent also discloses that water or fluid from a reservoir may be circulated through the water brake to control the operational characteristics of the dynamometer. Hoffstrom, in U.S. Pat. No. 2,551,677, "Hydraulic Brake Actuating Means", further discloses a valve configuration for a fluid brake which controls the circulatory flow of fluid through the fluid brake to and from a reservoir.
While such prior art dynamometers or fluid brakes are believed to function well, a need has remained for a simple unitary control mechanism for controlling and adjusting fluid flow to and from a reservoir through a fluid brake. The present invention constitutes such an improved, unitary control and adjustment mechanism.